silicone sealshower tray

How long would it take a Tiler to properly regrout (remove old grout and reapply new grout), as well as remove old silicone and re-silicone within a moderately sized shower enclosure, approx 118cm L x 90cm W x 220 cm H? Pictures also attached. If only a few of the tiles show hairline cracks...

Sealing a shower tray I'm fitting a new shower, 3 walls and a sliding door in a frame. The tray will be tanked to the wall with tanking tape, then tiled. I've read in a few places to seal the between try the tray and tile where the frame meets the wall before adding the door frame so that water...